Throughout antiquity, Egypt’s standing relied on its agricultural wealth and, therefore, on the Nile. Agriculture had not been the original basis of subsistence, but evolved, together with the land itself, during the millennia after the last Ice Age ended around 10,000 BC, expanding greatly from about 4500 BC onward.
By 3100 BC the Nile Valley and Delta had coalesced into a single entity that was the world’s first large nation state. As well as providing the region’s material potential, the Nile and other geographical features influenced political developments and were significant in the development of Egyptian thought.
The land continued to develop and its population increased until Roman times. Important factors in this process were unity, political stability, and the expansion of the area of cultivated land. The harnessing of the Nile was crucial to growth.
It is uncertain how early and by how much the inundation was regulated. By the Middle Kingdom (c.1975-1640 BC) basin irrigation, in which large sections of the floodplain were managed as single units, was well established, but it may not have been practised in the Old Kingdom (c.2575-2150 BC), when the great pyramids were built. The only area where there was major irrigation work before Graeco-Roman times was the Faiyum, a lakeside oasis to the west of the Nile. Here Middle Kingdom kings reclaimed land by controlling the water flow along a side river channel and directing it to irrigate extra land while lake water levels were lowered. Their scheme did not last.